Based on the U.S. Bureau of the Census definition, this includes dry land and land temporarily or partially covered by water, such as marshlands, swamps and river flood plains, systems, sloughs, estuaries and canals less than 1/8 of a statute mile (0.2 kilometers) in width and lakes, reservoirs and ponds less than 1/16 square mile (0.16 square kilometers) in area. [For Alaska, 1/2 mile (0.8 kilometers) and 1 square mile (2.60 square kilometers) are substituted for these values]. The net land area excludes areas of oceans, bays, sounds, etc., lying within the 3 mile (4.8 kilometers) U.S. jurisdiction as well as inland water areas larger than indicated above. (FHWA2)